1. Technical Field
The present disclosure relates to a display substrate and a method of manufacturing the display substrate, and more particularly, to a display substrate including a light-emitting element and a method of manufacturing the display substrate.
2. Discussion of the Related Art
An organic light-emitting diode (OLED) apparatus includes two electrodes and a light-emitting layer disposed between the two electrodes. The light-emitting layer may comprise an organic material. Excitons are formed in an organic light-emitting layer. The excitons are formed by combining electrons injected from a first electrode through the organic light-emitting layer and holes injected from a second electrode through the organic light-emitting layer. The excitons emit energy in a form of light. The OLED apparatus does not require a separate light source. Thus, the OLED apparatus consumes less power, and maintains an enhanced response time, viewing angle, and contrast ratio in comparison with a liquid crystal display (LCD) apparatus.
An OLED apparatus of an active matrix type includes a switching transistor connected to a signal line and a driving transistor connected to the switching transistor. The switching transistor controls a data voltage provided from the signal line. The driving transistor receives the data voltage from a control electrode of the switching transistor. The driving transistor applies the data voltage to a light-emitting element. The driving transistor requires high mobility and high stability to transmit sufficient current. An active pattern of the driving transistor can be formed using polycrystalline silicon or microcrystalline silicon. However, the polycrystalline silicon or the microcrystalline silicon is formed by crystallizing amorphous silicon at a high temperature. During the high temperature process, upper and lower patterns of the substrates may be misaligned, the uniformity of the polycrystalline silicon or the microcrystalline silicon may be deteriorated, and a leakage current may be generated in the active pattern of the driving transistor. As such, a need exists for a display substrate having a driving transistor with an improved electrical characteristic.